We utilise spray-coating under ambient conditions to sequentially deposit compact-TiO2, mesoporous-TiO2, CH3NH3PbI(3−x)Clx perovskite and doped spiro-OMeTAD layers, creating a mesoporous standard architecture perovskite solar cell (PSC). The devices created had an average power conversion efficiency (PCE) of 9.2% and a peak PCE of 10.2%; values that compare favourably with control-devices fabricated by spin-casting that had an average efficiency of 11.4%. We show that our process can be used to create devices having an active-area of 1.5 cm2 having an independently verified efficiency of 6.6%. This work demonstrates the versatility of spray-coating as well as its potential as a method of manufacturing low-cost, large-area, efficient perovskite devices.

We use ultrasonic spray-coating to fabricate caesium containing triple-cation perovskite solar cells having a power conversion efficiency up to 17.8%. Our fabrication route involves a brief exposure of the partially wet spray-cast films to a coarse-vacuum; a process that is used to control film crystallisation. We show that films that are not vacuum exposed are relatively rough and inhomogeneous, while vacuum exposed films are smooth and consist of small and densely-packed perovskite crystals. The process techniques developed here represent a step towards a scalable and industrially compatible manufacturing process capable of creating stable and high-performance perovskite solar cells.

An encapsulation system comprising of a UV‐curable epoxy, a solution processed polymer interlayer, and a glass cover‐slip, is used to increase the stability of methylammonium lead triiodide (CH3NH3PbI3) perovskite planar inverted architecture photovoltaic (PV) devices. It is found this encapsulation system acts as an efficient barrier to extrinsic degradation processes (ingress of moisture and oxygen), and that the polymer acts as a barrier that protects the PV device from the epoxy before it is fully cured. This results in devices that maintain 80% of their initial power conversion efficiency after 1000 h of AM1.5 irradiation. Such devices are used as a benchmark and are compared with devices having initially enhanced efficiency as a result of a solvent annealing process. It is found that such solvent‐annealed devices undergo enhanced burn‐in and have a reduced long‐term efficiency, a result demonstrating that initially enhanced device efficiency does not necessarily result in long‐term stability.

The development of scalable deposition methods for perovskite solar cell materials is critical to enable the commercialization of this nascent technology. Herein, we investigate the use and processing of nanoparticle SnO2 films as electron transport layers in perovskite solar cells and develop deposition methods for ultrasonic spray coating and slot-die coating, leading to photovoltaic device efficiencies over 19%. The effects of postprocessing treatments (thermal annealing, UV ozone, and O2 plasma) are then probed using structural and spectroscopic techniques to characterize the nature of the np-SnO2/perovskite interface. We show that a brief “hot air flow” method can be used to replace extended thermal annealing, confirming that this approach is compatible with high-throughput processing. Our results highlight the importance of interface management to minimize nonradiative losses and provide a deeper understanding of the processing requirements for large-area deposition of nanoparticle metal oxides.

Back-contact PSCs are fabricated by depositing charge-selective electrodes and MAPbI3 into micron-sized polymeric grooves, micro-modules are formed by serially-connecting grooves.